EGR 103/DAQ 2

This page contains pictures and graphs related to DAQ 2 for EGR 103. It has been updated for Spring 2015.

Notes

As before, if the system seems to not recognize Dev1, try Dev2 instead.

Pauses

There are pause commands in the code which will cause the program to...pause - specifically when the program first runs to check the lights. You will need to hit a key to un-pause the program. The way to see if the program is paused is to look at the bottom left corner of your MATLAB window - it will tell you if it is paused.

Graph Labels

For this particular assignment, you do not need axis labels. You need a title on each subplot, however.

Circuit for BasicAOutput

Circuit layout for BasicAOutput.

Circuit for BasicAIO

Circuit layout for BasicAIO (two measurements).

Graph from BasicAIO

Graph showing outputs when

Vout0 = 2.5+2.5*sin(2*pi*k/100);
Vout1 = 2.5+2.5*cos(2*pi*k/100);

That is,

\( \begin{align} V_{out,\,0}=2.5+2.5\sin\left(\frac{2\pi k}{100}\right)\\ V_{out,\,1}=2.5+2.5\cos\left(\frac{2\pi k}{100}\right) \end{align} \)

Circuit for AIO

Circuit layout for AIO (six measurements).

Graph from AIO

Graph showing outputs from six measurement channels.

Codes

Pasting codes from PDF files is...a bad idea. Here are the text versions of some of the codes in the assignment.

BasicAOutput.m

% Clear out workspace
clear

% Clear out DAQ objects
delete(daqfind)

% Create Analog Output Object
AO = analogoutput('nidaq', 'Dev1');

% Change sample rate
set(AO, 'SampleRate', 500);

% View Analog Output Object
AO

% Add channels to Analog Output Object
addchannel(AO, [0 1])







% Write values to output channels
putsample(AO, [5 5])
pause
putsample(AO, [0 0])

% Use loop to set several different voltages
for k=1:300
    % Calculate voltages for each channel
    Vout0 = 2.5+2.5*sin(2*pi*k/100);
    Vout1 = 2.5+2.5*cos(2*pi*k/100);
    % Put voltages to each output channel
    putsample(AO, [Vout0 Vout1])
    % leave line 31 blank for now
    % leave line 32 blank for now
    pause(0.02)
end








% Turn all outputs off
putsample(AO, [0 0])

BasicAIO.m

% Clear out workspace
clear

% Clear out DAQ objects
delete(daqfind)

% Create Analog Output Object
AO = analogoutput('nidaq', 'Dev1');

% Change sample rate
set(AO, 'SampleRate', 500);

% View Analog Output Object
AO

% Add channels to Analog Output Object
addchannel(AO, [0 1])

% Create Analog Input Object
AI = analoginput('nidaq', 'Dev1')

% Add channels to Analog Input Object
addchannel(AI, [0 4])

% Write values to output channels
putsample(AO, [5 5])
pause
putsample(AO, [0 0])

% Use loop to set several different voltages
for k=1:300
    % Calculate voltages for each channel
    Vout0 = 2.5+2.5*sin(2*pi*k/100);
    Vout1 = 2.5+2.5*cos(2*pi*k/100);
    % Put voltages to each output channel
    putsample(AO, [Vout0 Vout1])
    % Read voltages from all input channels
    Voltages(k,:) = getsample(AI);
    pause(0.02)
end

% Plot voltages versus index
n = 1:k;
Vleft  = Voltages(:,1);
Vright = Voltages(:,2);
plot(n, Vleft, 'g', n, Vright, 'r')
legend('Green LED', 'Red LED', 0)

% Turn all outputs off
putsample(AO, [0 0])

Example Commands to Parse Data Set for Small Green and Red LEDs

load SmallData
SmallGreenTotal = SmallVoltages(:,1);
SmallGreenRes   = SmallVoltages(:,2);
SmallGreenLED   = SmallVoltages(:,3);
SmallRedTotal   = SmallVoltages(:,4);
SmallRedRes     = SmallVoltages(:,5);
SmallRedLED     = SmallVoltages(:,6);

Subplot Structure for Plotting Code

The code below includes the commands for the small green LED assuming the variable names given in the code above.

subplot(3,2,1)
% small green plotting commands
plot(SmallGreenTotal, SmallGreenTotal, 'k-',...
     SmallGreenTotal, SmallGreenRes,   'b-',...
     SmallGreenTotal, SmallGreenLED,   'g-') 
title('Small Green LED')
grid on 

subplot(3,2,2)
% small red plotting commands

subplot(3,2,3)
% large green plotting commands

subplot(3,2,4)
% large red plotting commands

subplot(3,2,5)
% rect green plotting commands

subplot(3,2,6)
% rect red plotting commands

Questions

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